Means for varying areas of plungers of hydraulic machines.



Patented lune Il, |901.

.X w m No. 676,25l.

W. J. HAGMAN. MEANS FOB VARYING AREAS (11F PLUNGEBS 0F HYDRAULIC MACHINES.

(Applicatiun led Nv. 7, 1900.)

(No Modelv.)

NITED STATES PATENT OFFICE.

WILLIAM JOSEPH HAGMAN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE NILES, BEMENT, POND COMPANY, OF SAME PLAGE AND JERSEY CITY, NEW JERSEY.

MEANS FOR VARYING AREAS OF PLUNGERS OF HYDRAULIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 67' 6,251 dated June 11, 1901.

Application tiled November 7,1900. Serial No. 35,748. (No model.)

To a/ZZ whom it may concern,.-

Be it known that I, WILLIAM JOSEPH HAG- MAN, a citizen of the United States, residing in Philadelphia, Pennsylvania,have invented certain Improvements in Means for Varying the Areas of Plungers of Hydraulic Machines, of which the following is a specification.

My invention relates to certain improvements in hydraulic machines in which differ- Io ent pressures are desirablesuch, for instance, as hydraulic riveting-machines.

The object of my invention is to obtain different pressures without multiplying the cylinders and withoutl complicating the valve I5 mechanism, at the same time providing a machine which can be packed without dis-` mantling the parts.

In the accompanying drawings, Figure lis a side View of the upper portion ofa hydraulic 2b riveting-machine, illustrating my invention. Fig. 2 is a view similar to Fig. 1, showing parts in section. Figs. 3, 4, and 5 are perspective views of detached parts of the machine; and Fig. 6 is a sectional view on the 25 line 6 6, Fig. 1, showing thepassage between thevalve mechanism and the interior of the cylinder.

In the drawings I have shown my invention applied to a riveting-machine, but it will be 3o understood that it may be applied to any iiuidoperated machine requiring more than a single pressure.

P is a standard, and P is a stake, forming part of a frame of a riveting-machine.

A is a frame secured to the standard P. Forming part'of this frame in the present instance is the cylinder A. and the guideways a a for the riveting-slide B. On the riveting-slide B and stake P are the ordinary riveting-dies. A cylinder A has a bushing a and a stuffing-box Qc, and extending throughthis box into the forward end of the cylinder is the main plunger B, which is connected to the rear of the riveting-slide B by a bolt or bolts. (Not shown in the drawings.)

Mounted in the frame A above theslide B is a return-cylinder C, having a plunger C bearing against the forward end of the plunger B.

The cylinder A is open at the rear end, having an inwardly-projecting portion or ange,

cylinder is an auxiliary piston G, having a which holds in place a flanged bushing b, there being also a stuffing-box o3 at the said rear end. Extending into the rear end of the head Gl at its inner end, in the present instance made separate from the piston and having a threaded portion screwed into the piston G, which is tubular for the reception of a second auxiliary piston E.

In the interior of the tubular piston G is an annular rib g', having back of it a bushing c, there being a stung-box m2 on the outer end of said piston through which the piston E extends. This piston has a head e forming a shoulder, and a threaded stem E' extending beyond the head e, the threads thereon being .interrupted in the present instance, as shown in Fig. 3. The outer end e of the piston is squared for the reception of a wrench by which the piston can be turned.

The main plunger B is hollow and has an internal screw-thread.

D is a nut having an external screw-thread, a flange, and an internal interrupted thread designed to mesh with the threads of the stem E. Thel nut D can be attached in any suitable I'nanner to the rear of the plunger B.

Valve mechanism N, operated by the lever M, is attached to the side of the machine, and a passage Q connects it with the main cylinder, as shown in Fig. 6. The return-cylinder receives its pressure duid from any point in the system.

The operation of my device is as follows: In order to obtain the maximum Working pressure at the riveting-dies, the screw-stem E is detached from the nut D by turning the piston E. This allows the full pressure of the Water admitted to the space W to be exerted on the plunger B. This water-pressure is also exerted on the face of the stem E', the head or shoulder e keeping the piston E in the piston G by engaging the rib g thereof. By turning the piston E when it is at the forward end of its stroke and when the plunger B,with the slide B', is in the out position shown `in the drawings the threaded stem E will engage the threads of the nut D, coupling it to the plunger B. When now the water is admitted to the space W, the piston E will move forward with the main plunger B, and the IOO available working pressure at the dies will be diminished by as much as the active area,of

the face of the plunger B has been diminished by the area of the piston E. If now the plunger B is moved in contact with the head of` single plunger is used, which when acting alone exerts its maximum pressure, when coupled toone auxiliary piston exerts an intermediate pressure, and when a second piston is attached the minimum pressure is attained. The application of this idea is not coniined to riveting-machines, since it will be understood by those skilled in the art that it maybe applied to any of the Well-known forms of hydraulic or other machinery-such as punches, shears, &c.-in which a variable pressure at the plunger is required.

It will be understood that I do not confinemyself to the use of interrupted threads in coupling the auxiliary pistons to the main plunger and to one another, as I may employ any other mechanical device tov accomplishthis end.

It is to be noted that by my improved device the pistons are all outside packed, the

various stung-boxes being `in positions which can easily be reached and overhauled without disturbing any other part of the ma` chine.

I claimas my inventionl. In a riveting or similar hydraulic ma-v..

chine capable of exerting variable pressures,

the combination of a frame, a cylinder there- 4 on., a'moving slide, a plunger connected to said slide, and means extending through thev cylinder to the Voutside of the same for vary-Q ingthe area of said plunger exposed to the motive fluid, said means being positively secured to the plunger and held thereto during the entire length of stroke, substantially a described.

2. The -combination in a riveting or similar hydraulic machine, of a frame, a moving slide l and a cylinder thereon, a plunger operatingV in said cylinder, a piston and mechanism attached thereto extending through the cylinder to the outside o f the same, said pistonv being constructed to be coupled to or released from said plunger at will, the relative posi-- tions of the piston and of the plunger remain-v ing the same throughout the entire stroke, substantially as described.

IThe combination in a riveting or similar hydraulic machine, of a frame, guides thereon, .a movingl slide operated in said guides and having connected to it a main plunger, a cylindero-n the frame for said plunger, auxiliary pistons in the cylinder, and mechanism extending to the outside of the cylinder for coupling and disconnecting said pistons and the plunger, the relative positions of the'pistons and the plunger remaining unaltered during operation throughout the entire stroke of said plunger, substantially as described.

4. A riveting or similar hydraulic machine consisting of a frame, a moving slide and a cylinder thereon, a hollow piston in the cylinder connected to the slide and having screwthreads in its interior, a second piston in the cylinder also having screw-threads thereon and means for turning the said second piston whereby the two pistons may be coupled together, substantially as described.

5. In a riveting or similar hydraulic machine, the combination of a frame, a cylinder thereon, a plunger in the cylinder having attached to it a moving slide, guides for said slide, two auxiliary `pistons in said cylinder, one within the other, a threaded `stem on one of said pistons and threads on the plunger :whereby either one or both 'of the auxiliary pistons may be coupled to the plunger, substantially as described.

6. The combination in a riveting or similar hydraulic machine, of a supporting-frame, a moving slide and a cylinder thereon, a plunger in the cylinder connected to the moving slide, said plunger having an internal interrupted thread, a piston in the cylinder havl ing an interrupted thread thereon, and means for turning the piston whereby, when the pis; tons have been moved together, they may be coupled, substantially as described.

7. The combination in a riveting or similar hydraulic machine of a frame, a moving slide anda cylinder on said frame, a hollow piston in the cylinder connected to the moving slide, a nut in said piston having internal inter'- rupted threads, two auxiliary pistons in the said cylinder, one Within the other, the inner one having a stem with interrupted threads thereon, said pistons being so constructed that when the outer section of the threaded stem of the inner piston engages the plunger, said plunger and the inner piston are coupled together, and when the vinner section of the threaded stem of said piston engages the plunger, the two auxiliary pistons are cou--l pled to said plunger, substantially as described.

8. In a riveting or similar hydraulic machine,the combination of a supporting-frame, a cylinder on one arm thereof, guides, a moving slide constructed to operate inthe guides and having attached to it a plunger which works in said cylinder, auxiliary pistons in the cylinder, with means for coupling either one or allof said pistons to the plunger, and

` outside-packed stuiiing-boxes for the .plunger and for each of the pistons, substantially as described.

ymoving slide and a return-cylinder, of a main 'cylinder flanged internally at the rear end, a hollow plunger in the forward end of said cylinder and attached to the moving slide, a tubular piston flanged both internally and externally, a solid piston within the tubular piston and having a shoulder and means for coupling either one or both of said pistons to said plunger wherebythree dilerent pressures for riveting or other service may be obtained, substantially as described.

l0. In a riveting or similar hydraulic machine,the combination of a supporting-frame, a cylinder on one arm thereof, guides, a m0ving slide constructed to operate in the guides and having attached to it a plunger which works in said cylinder, auxiliary pistons in the cylinder, with means for coupling either one or all of said pistons to the plunger, and a single passageway opening into the cylinder, between the pistons, through which the motive fluid may en ter and exhaust, substantially as described. I

In testimonyT whereof I have signed my name to this specication in the presence of two subscribing witnesses.

WILLIAM JOSEPH I-IAGMAN;

Witnesses: p

WILLIAM E. BRADLEY, Jos. H. KLEIN. 

